The Third Generation Partnership Project Two (3GPP2) standard provides a compatibility standard for cellular mobile telecommunications systems. The 3GPP2 standard ensures that a mobile station (MS), or access terminal (AT), (hereinafter collectively referred to as an MS) operating in a cdma2000 (Code Division Multiple Access 2000) communication system (such as a 1× system or a DO system) can obtain communication services when operating in a system manufactured according to the standards. To ensure compatibility, radio system parameters and data transfer procedures are specified by the standards, including protocols governing digital control messages and bearer traffic that are exchanged over an air interface.
The 3GPP2 standards provide, in the X.P0022, A.S00019, and S.R0083 specifications, for delivery of a Broadcast-Multicast Service (BCMCS) by a cdma2000 communication system to MSs serviced by the system and subscribed to the Service. For example, a BCMCS may deliver a broadcast-multicast flow of audio, video, and/or data associated with a multimedia program such as a Cable News Network (CNN) newscast or an Home Box Office (HBO) show. When a MS activates in a communication system that provides a BCMCS, the MS may request access to one or more broadcast-multicast flows associated with the BCMCS by indicating to the communication system, and in particular to a BCMCS Controller, a willingness to receive multicast data associated with the BCMCS flow. By registering for the BCMCS, and for particular broadcast-multicast flows, the MS joins a broadcast/multicast group associated with those flows.
In response to receiving an access request from a MS for a broadcast-multicast flow, the BCMCS Controller conveys to the MS multiple identifiers (BCMCS_FLOW_ID and BAK_ID) associated with that flow, that is, with the particular program, such as CNN or HBO, subscribed to by the MS and an encryption key (EncrBAK) used to encrypt the audio, video, and/or data associated with that flow. When the BCMCS Controller receives BCMCS data associated with the flow, the BCMCS Controller may cause the data to be encrypted using the EncrBAK key and to be broadcast via a Base Station (BS) or an Access Network (AN) (hereinafter collectively referred to as a BS) servicing the MS. Each subscribed MS may then decrypt the broadcast audio, video, and/or data using the provided key and display the audio, video, and/or data to the user of the MS. When an MS subscribes to multiple BCMCS flows, the MS is provided a Flow ID and an encryption key associated with each such flow. The user of the MS may then select, at any time, which broadcast-multicast flow of the multiple broadcast-multicast flows to decrypt and to listen to or watch.
Currently, the 3GPP2 standards do not regulate a quantity or quality of broadcast-multicast flows conveyed by a BCMCS Controller to a BS and subscribed to by MSs serviced by the BS. That is, in providing broadcast-multicast flows associated with Broadcast-Multicast Services to a BS, the BCMCS Controller may have to provide all flows subscribed to by all MSs serviced by the BS regardless of the available bandwidth or channel conditions at the BS. This unregulated conveyance of flows can produce congestion in the BS due to a lack of available bandwidth for a broadcast of all received flows. As a result, the BS may end up arbitrarily blocking some of the received flows and/or arbitrarily reducing a Quality of Service (QoS) of one or more concurrently received flows. In addition, the BS is unaware of subscription information related to each MS subscribing to one or more such flows and serviced by the BS. For example, when an MS subscribes to a BCMCS, the MS may further specify a particular QoS for the Service, for example, to a Gold, Silver, or Bronze plan, or may understand that a particular BCMCS will be provided at a predetermined QoS. When the BS arbitrarily blocks received flows or arbitrarily reduces QoS, the BS may block broadcast-multicast flows subscribed to by a large number of subscribers while broadcasting broadcast-multicast flows with a low number of subscribers or may reduce QoS to an unacceptably low level. The result is frustrated subscribers and angry system operators.
Therefore, a need exists for a method and apparatus for regulating the delivery of BCMCS by a BCMCS Controller to a BS.